Hi there
I get a slight bit (no more than a laptop) of fan noise when using an external monitor and running two concurrent VM's - it does get about as warm as a largish mobile phone (Samsung S5) but certainly not Hot and not unbearable when holding or using on a lap while watching Video, Sky Go etc.

Nothing to worry about - I've often had mine running continuously for two or three days at a time - no probs whatsoever.